Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L63/00—Compositions of epoxy resins; Compositions of derivatives of epoxy resins
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G59/00—Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
  • C08G59/18—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing
  • C08G59/40—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing characterised by the curing agents used
  • C08G59/4007—Curing agents not provided for by the groups C08G59/42 - C08G59/66
  • C08G59/4014—Nitrogen containing compounds
  • C08G59/4021—Ureas; Thioureas; Guanidines; Dicyandiamides
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G59/00—Polycondensates containing more than one epoxy group per molecule; Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups
  • C08G59/18—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing
  • C08G59/40—Macromolecules obtained by polymerising compounds containing more than one epoxy group per molecule using curing agents or catalysts which react with the epoxy groups ; e.g. general methods of curing characterised by the curing agents used
  • C08G59/4007—Curing agents not provided for by the groups C08G59/42 - C08G59/66
  • C08G59/4014—Nitrogen containing compounds
  • C08G59/4042—Imines; Imides
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/18—Manufacture of films or sheets
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/24—Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L79/00—Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen with or without oxygen or carbon only, not provided for in groups C08L61/00 - C08L77/00
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2363/00—Characterised by the use of epoxy resins; Derivatives of epoxy resins
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2203/00—Applications
  • C08L2203/16—Applications used for films
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2205/00—Polymer mixtures characterised by other features
  • C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
  • C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials
  • C08L2666/14—Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
  • C08L2666/20—Macromolecular compounds having nitrogen in the main chain according to C08L75/00 - C08L79/00; Derivatives thereof

Definitions

• This disclosure relates to epoxy compositions including polycarbodiimide species, in particular epoxy compositions useful in making surfacing films with good paint stripper resistance and micro crack resistance.
• the present disclosure provides a composition
• a composition comprising: a) a curable epoxy resin; and b) 0.01-30% by weight of a polycarbodiimide according to Formula I:
• n is an integer between 0 and 100, and wherein each R is independently selected from aromatic and aliphatic groups which contain between 1 and 24 carbons and which are optionally substituted.
• the composition typically comprises 0.1-20% by weight of the polycarbodiimide and may in some embodiments comprise 0.1-10% by weight of the polycarbodiimide, in some embodiments 0.5-5% by weight of the polycarbodiimide, and in some embodiments 1-3% by weight of the polycarbodiimide.
• n is at least 1.
• n is at least 2.
• R contains between 3 and 12 carbons.
• all R groups are aromatic.
• all R groups are phenyl or phenylene.
• the present disclosure provides compositions which are the composition described above being partially cured or fully cured. In some embodiments the present disclosure provides sheet materials made of such cured, uncured or partially cured materials. In some embodiments the present disclosure provides composite parts comprising the cured composition. In some embodiments the present disclosure provides composite parts having an outermost surface comprising the cured composition.
• substituted means, for a chemical species, group or moiety, substituted by conventional substituents which do not interfere with the desired product or process, e.g., substituents can be alkyl, alkoxy, aryl, phenyl, halo (F, CI, Br, I), cyano, nitro, etc.
• the present disclosure provides epoxy compositions which, in some embodiments, may be used to form surfacing films demonstrating increased resistance to paint strippers.
• the present disclosure provides uncured epoxy compositions and cured epoxy compositions that resulting from the cure of the uncured epoxy compositions provided herein.
• the uncured epoxy composition may include any suitable epoxide resin, including epoxide monomers or epoxide prepolymers, and any suitable hardener, typically an amine hardener.
• the uncured epoxy composition may include any suitable crosslinker, in addition to those described below.
• the uncured epoxy composition includes no crosslinker other than those described below.
• the uncured epoxy composition includes a carbodiimide species, which is typically a polycarbodiimide species.
• the polycarbodiimide species is isocyanate capped, more typically, the isocyanate capped polycarbodiimide species is according to Formula I:
• n is an integer, typically between 0 and 100, more typically between 1 and 20, which may vary or may be a single value; and where each R is independently selected from aromatic and aliphatic groups which may optionally be substituted and which typically contain between 1 and 24 carbons, more typically between 3 and 12 carbons.
• all R groups are aromatic.
• all R groups are phenyl or phenylene.
• the isocyanate capped polycarbodiimide species is a phenyl isocyanate capped toluene diisocyanate polycarbodiimide.
• the uncured epoxy composition includes an oxazolidone ring-containing epoxy resin. In some embodiments, the uncured epoxy composition includes both an oxazolidone ring-containing epoxy resin and a polycarbodiimide species as described above.
• uncured or cured epoxy compositions according to the present disclosure may additionally comprise fillers, pigments, carbon particles, or carbon nanotube materials.
• uncured epoxy compositions according to the present invention may be formed into films by any suitable method.
• such films may be used as surfacing films.
• such films may be used as surfacing films in the manufacture of fiber-matrix composite parts. Typically, such a surfacing film is cured during cure of the composite matrix, and becomes a cured-in component of the composite part forming the outer surface of the composite part.
• such films may be used to form a multi-layered construct with polyvinylidene fluoride (PVDF) films, which may in some embodiments be used as surfacing films.
• PVDF polyvinylidene fluoride
• such films may be used in applications such as and including those described in U.S. Pat. App. Nos. 12/761162, 12/761212, 12/625002, 12/637879 and 12/637915.
• epoxy compositions according to the present invention may be used as curable adhesives.
• epoxy compositions according to the present invention may be used as matrix materials in prepregs or in fiber-matrix composite parts
• Pencil Hardness Gouge hardness of the test surface was measured according to ASTM D3363-05. Hardness was reported for the hardest pencil that left the test surface uncut for a stroke length of at least 3 mm, using pencils obtained from General Pencil Company, Redwood City, California.
• Paint Stripper Uptake The test panel was weighed and an area of 4 cm by 5 cm was marked. Four grams of a benzyl alcohol-based paint stripper, type "CEE BEE E2012A", obtained from Cee Bee Aviation Products, McGean-Rohco, Inc. Cleveland, Ohio, was brushed onto the test area. After 24 hours at 70°F (21.1°C) the paint stripper was manually scraped off the test area, and the panel then rinsed with iso-propyl alcohol. After drying the panel for 60 minutes at 70°F (21.1°C) it was reweighed. The increased weight of the test panel was reported as paint stripper uptake.
• CEE BEE E2012A obtained from Cee Bee Aviation Products, McGean-Rohco, Inc. Cleveland, Ohio
• Micro crack testing was performed on primed and painted test panels.
• the primer was CA 7501 two part fluid resistance gray applied as a single light coat.
• the paint was 8800 three part white topcoat, applied to the primed panel in two coats.
• the paint and primer are available from PRC Desoto, Sylmar, California. Mixing and drying were performed as per manufacturer's instructions.
• Micro crack testing was conducted in a thermal shock chamber, a two chamber oven with a shuttle that can be moved between the two chambers. One chamber was set at -54°C (-65 °F) and the other at 49°C (120°F).
• the shuttle is programmed to sit in each chamber for 10 minutes before moving back to the other chamber. Samples were placed on a rack which was loaded onto the shuttle. The samples were cycled between the two chambers between 3000 and 4000 cycles. The panels were inspected for micro cracks using an optical microscope at a magnification of 16x. A known area is inspected and the cracks per linear cm were calculated. Zero cracks observed after all cycles were complete was rated a "pass", less than or equal to 0.25 cracks per linear cm was rated a "marginal pass”, and greater than 0.25 cracks per linear cm was rated a "fail".
• C-150 HP Agglomerates of multi-walled carbon nanotubes, available under the trade designation "BAYTUBES C-150 HP", from Bayer MaterialScience AG, Leverkusen, Germany.
• CG-1400 A micronized dicyandiamide, having an approximate amine equivalent weight of 21 grams/equivalent, available under the trade designation "AMICURE CG-1400", from Air Products and Chemicals Incorporated, Allentown, Pennsylvania.
• DEH-85 An unmodified phenolic hardener having an active hydrogen equivalent weight of approximately 265 grams/equivalent, available under the trade designation "DEH-85”, from Dow Chemical Company, Midland, Michigan.
• EP 7200 A modified bisphenol-A epoxy resin with an approximate equivalent weight of approximately 207.5 grams/equivalent, available under the trade designation "EPALOY 7200", from CVC Specialty Chemicals Inc., Moorestown, New Jersey,.
• Epon 826 A low viscosity liquid bisphenol A based epoxy resin having an approximate equivalent weight of 182 650 grams/equivalent, available under the trade designation "EPON 826", from Hexion Specialty Chemicals, Columbus, Ohio.
• EPON 1002F A bisphenol-A poly epoxide resin having a functionality of 2 and an approximate epoxy equivalent weight of 650 grams/equivalent, available under the trade designation "EPON 1002F", from Hexion Specialty Chemicals, Columbus, Ohio.
• EPON 1004F A bisphenol-A poly epoxide resin having a functionality of 2 and an approximate epoxide equivalent weight of 875 grams/equivalent, available under the trade designation "EPON 1004F", from Hexion Specialty Chemicals.
• MEK Methyl ethyl ketone.
• MX- 120 A diglycidyl ether of Bisphenol-A epoxy resin butadiene-acrylic co-polymer core shell rubber having an approximate epoxy equivalent weight of 243
• MY-720 A tetra- functional liquid epoxy, having an approximate epoxy equivalent weight of 125.5 grams/equivalent, available under the trade designation "ARALDITE MY-720", from Huntsman Advanced Materials America Incorporated, The Woodlands, Texas.
• PCDI 77.5% A phenyl isocyanate capped toluene diisocyanate polycarbodiimide, having a 2: 1 ratio by weight toluene diisocyanate :phenyl isocyanate, at approximately 77.5 % by weight in toluene, prepared as follows: To a clean dry 3 -liter flask under a nitrogen atmosphere, 600 g of toluene diisocyanate, 205 g of phenyl isocyanate, and 184 g of toluene were charged.
• PCDI 40% A phenyl isocyanate capped toluene diisocyanate polycarbodiimide, having a 2: 1 ratio by weight toluene diisocyanate :phenyl isocyanate, at approximately 40 % by weight in toluene, prepared as follows: To a clean dry 2-liter flask under a nitrogen atmosphere, 320 g of toluene diisocyanate, 109.4 g of phenyl isocyanate, and 480 g of toluene were charged.
• the solution was mixed, to which a catalyst premix of 1.84 grams of 3 -methyl- l-phenyl-2-phospholene-l -oxide in 12.5 grams of toluene, was then added.
• the batch was slowly heated, for approximately 60 minutes, to 230°F, then held at this temperature for 3 hours. Using infrared spectroscopy to confirm the isocyanate had been consumed, the mixture was then cooled 75 °F.
• PKHP A micronized phenoxy resin, having a number average molecular weight (MN) 10,000-16,000, and a hydroxy equivalent weight 284 grams/equivalent, available under the trade designation "PAPHEN PKHP-200", from Phenoxy Associates, Rock Hill, SC USA.
• R-960 A rutile titanium dioxide pigment, available under the trade designation "TI-PUR R-960", from E.I. du Pont de Nemours & Company, Wilmington, Delaware.
• RA95 A high viscosity, Bisphenol A epoxy resin modified butadeine-acrylonitrile elastomer having an approximate epoxy equivalent weight of 202.5 grams/equivalent, available under the trade designation "Hypox RA95" from CVC Specialty Chemicals Inc., Moorestown, New Jersey.
• SU-2.5 A bisphenol-A polyepoxide resin having a functionality of 2.5 and an
• SU-8 A bisphenol-A polyepoxide resin having a functionality of 8 and an approximate epoxy equivalent weight of 212.5 grams/equivalent, available under the trade designation "EPON SU-8", from Hexion Specialty Chemicals.
• U-52 An aromatic substituted urea (4,4'-methylene bis (phenyl dimethyl urea), having an approximate amine equivalent weight of 170 grams/equivalent, available under the trade designation "OMICURE U-52", from CVC Specialty Chemicals Incorporated.
• VYG A copper-phthalocyanine pigment, available under the trade designation
• VYNAMON GREEN 600734 from Heucotech Ltd., Fairless Hills, Pennsylvania.
• XAC-4151 An oxazolidone ring containing epoxy, having an approximate epoxy equivalent weight of 420 grams/equivalent, available under the trade designation "XAC- 4151", from Asahi Kasei, Kanto, Japan.
• thermosetting modified epoxy structural adhesive film having a base weight of approximately 0.05 pounds per square foot (lbs/ft 2 ) (244.2 grams per square centimeter (g/cm 2 )), available under the trade designation "SCOTCH- WELD STRUCTURAL ADHESIVE FILM, 0.05", from 3M Company, St. Paul, Minnesota.
• SM 905M A composite surfacing film, having a base weight of 0.020 lbs/ft 2 (171 g/cm 2 ), available under the trade designation "SURFACE MASTER 905M", from Cytec
• XAC-4151 was manually crushed with a pestle and mortar and charged into a 200 gram capacity plastic cup designed for use in a planetary mill, model "SPEED MIXER Model DA 400 FV", available from Synergy Devices Limited, Buckinghamshire, United Kingdom. 85: 15 MEK/toluene was added to the cup, which was then secured to the mill and rotated at 2,200 rpm until the mixture was dissolved, approximately 5 minutes. The cup was removed from the mill, to which MX-120, SU-2.5 and MY-720 were added, and the mixing continued for another 2 minutes at 2,200 rpm. The cup was again removed from the mill and CG-1400 and U-52 were added. The mixture was manually stirred to wet out the curatives and the cup returned to the mill for another 2 minutes at 2,200 rpm, until all components were homogeneously dispersed.
• Example 1 Example 1
• Epon 1002F was manually crushed with a pestle and mortar and charged into a 200 gram capacity plastic cup, to which MEK was added.
• the cup was placed in the planetary mill, and mixed at 2,200 rpm until dissolved, approximately 5 minutes.
• the cup was removed from the mill, to which MX-120, SU-2.5, MY-720 and PCDI were added, and the mixing continued for another 2 minutes at 2,200 rpm.
• the cup was again removed from the mill and CG-1400 and U-52 were added. The mixture was manually stirred to wet out the curatives and the cup returned to the mill for another 2 minutes at 2,200 rpm, until all components were homogeneously dispersed.
• Example 1 The process as described in Example 1 was repeated according to the composition listed in Table 1, wherein the Epon 1002F was replaced with XAC-4151.
• R-960, VYG and SU-2.5 were charged into a 200 gram capacity plastic cup.
• the cup was placed in the planetary mill, and mixed at 2,200 rpm for 2 minutes.
• the mixture was then milled in a three-roll paint mill for three passes and set aside.
• XAC-4151 was manually crushed with a pestle and mortar and added to a planetary mill cup, followed by MEK, and mixed in the planetary mill at 2,200 rpm until dissolved, approximately 5 minutes.
• the cup was removed from the mill, to which the R-960, VYG and SU-2.5 from the three-roll paint mill, followed by MX-120, MY-720 and PCDI were added.
• Example 3 was repeated, wherein the VYG was replaced with CNT.
• Example 5 was repeated, wherein the VYG was replaced with CNT.
• R-960, VYG, CG-1400, U-52 and Epon 826 were charged into a 200 gram capacity plastic cup.
• the cup was placed in the planetary mill, and mixed at 2,200 rpm for 2 minutes.
• the mixture was then milled in a three-roll paint mill for three passes and set aside.
• XAC4151 and SU-8 were manually crushed with a pestle and mortar and added to a planetary mill cup, followed by MEK, and mixed in the planetary mill at 2,200 rpm until dissolved, approximately 10 minutes.
• the cup was removed from the mill, to which the R-960, VYG, CG-1400, U-52 and Epon 826 from the three-roll paint mill, followed by MX-120, MY-720, F-1, RA-95 and PCDI 77.5% were added.
• the mixture was returned to the planetary mill, and the mixing continued for another 2 minutes at 2,200 rpm.
• the mixture was manually stirred to scrape the sides of the cup and returned to the planetary mill for another 2 minutes at 2,200 rpm, until all components were homogeneously dispersed.
• R-960, VYG, CG-1400, U-52 and Epon 826 were charged into a 200 gram capacity plastic cup.
• the cup was placed in the planetary mill, and mixed at 2,200 rpm for 2 minutes.
• the mixture was then milled in a three-roll paint mill for three passes and set aside.
• DER 6508 and SU-8 were manually crushed with a pestle and mortar and added to a planetary mill cup, followed by MEK, and mixed in the planetary mill at 2,200 rpm until dissolved, approximately 10 minutes.
• the cup was removed from the mill, to which the R-960, VYG, CG-1400, U-52 and Epon 826 from the three-roll paint mill, followed by MX-120, MY-720, F-1, RA-95, remaining Epon 826, toluene and PCDI 40% were added.
• the mixture was returned to the planetary mill, and the mixing continued for another 2 minutes at 2,200 rpm.
• the mixture was manually stirred to scrape the sides of the cup and returned to the planetary mill for another 2 minutes at 2,200 rpm, until all components were homogeneously dispersed.
• the resin compositions were notch bar coated onto a bleached silicone coated release liner, product # "23210 76# BL KFT H/HP 4D/6MH" Loparex, Inc,. Iowa City, Iowa, at a bar gap of 6 mil (152.4 ⁇ ).
• the coated liner was then allowed to dry for at least 1 hour at about 70° F (21.1° C).
• the vacuum bag was kept under full vacuum (28 inches of Hg) for the duration of the cure cycle, and the temperature was raised at 5°F per minute (2.8°C per minute) up to 350°F (177°C) and held at this temperature for 2 hours.
• Example 6 showed better resistance to degradation in various tests when challenged with paint stripper.
• Example 6 additionally demonstrated good micro crack resistance. This additional characteristic is believed to be result from limiting the amount of PCDI to an amount in the range of 0.5-5% or more specifically between 1% and 3%.

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• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Manufacturing & Machinery (AREA)
• Paints Or Removers (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Epoxy Resins (AREA)
• Laminated Bodies (AREA)
• Inorganic Chemistry (AREA)
• Application Of Or Painting With Fluid Materials (AREA)

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  • 2010-12-22 US US12/975,478 patent/US20110159266A1/en not_active Abandoned
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  • 2010-12-22 EP EP10803541.1A patent/EP2519583B1/en active Active
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